Heat Transfer to Laminar Boundary Layers With Variable Free-Stream Velocity

Heat-transfer coefficients have been determined for the laminar boundary layer of a two-dimensional subsonic flow of air over a flat plate. By the agency of blisters attached to the wind-tunnel wall the boundary layer, formed under almost constant free-stream velocity, was subjected to a strong acceleration which produced a three to four-fold increase in the free-stream velocity, followed by a moderate deceleration. Maximum velocities ranged from 260 to 900 fps. The heat-transfer results are correlated on the basis expected for laminar flow and it is further demonstrated that a prediction method based on constant fluid properties gives satisfactory correspondence with experiment.